U.S. Pat. No. 2,559,227 (Rieber) describes a device for triggering and focusing shots on a target point which is intended to coincide with a target to be destroyed, for example tissue in a living being, said device being also applicable to destroying lithiases. The device may comprise a truncated elliptical reflector 80 in which shock waves are generated by an electric arc or discharge between two electrodes 12 and 13 which are disposed to coincide at the internal focus of the elliptical reflector which is filled with a liquid 83 for transmitting shock waves, e.g. oil (see FIG. 3 and column 7 line 51 to column 9 line 30).
Similarly, French published patent specification number 2 240 795 describes a similar apparatus in which the liquid is constituted by water (page 3, lines 23 to 24).
French published patent specification number 2 502 485 describes a target-locating arm 18, 20 supporting an ultrasonic target-locating probe 10 at its free end. The locating arm includes six joints, each of which is provided with an angle of rotation detector 26, 28, 30, 32, 34, or 36 in order to establish a diagnosis by displaying a tomogram of the examined sample.
European published patent specification EP-O 169 311 describes a locating arm having a locating probe at its free end which is responsive to X-rays or to ultrasound, and which is mounted on an apparatus for triggering and focusing shots on a target point which is intended to be brought into coincidence with a target to be destroyed, for example a lithiasis. This device for triggering and focusing shots is constituted by a truncated elliptical reflector, with the shots being constituted by shock waves generated in the first focus of the elliptical reflector which focuses these shots on the second focus as described by Rieber in U.S. Pat. No. 2,559,227.
Thus, the difficulty resides in making the target located by the locating probe situated at the end of the locating arm coincide with the elliptical reflector's second focus which constitutes the target point, with said elliptical reflector being mounted on a support which is displaceable in three mutually perpendicular directions X, Y, and Z. The present inventors have discovered that it is necessary to know the initial or "reference" position in three dimensions of the device for triggering and focusing shots, e.g. an elliptical reflector, and to coordinate said initial "reference" position with the initial "reference" position of the locating arm.
European patent specification number 0 169 311 neither describes nor suggests any such approach.
Thus, an aim of the present invention is to solve a new technical problem consisting in providing a solution capable of coordinating the initial or "reference" position in three dimensions of a device for triggering and focusing shots on a target point which is to be brought into coincidence with a target to be destroyed, e.g. a lithiasis, with the initial or "reference" position of an arm for locating the position of said target, thereby considerably increasing the accuracy of target location and bringing the target located by the locating probe at the end of the locating arm into coincidence with the target point as determined by the device for triggering and focusing shots and thus, unexpectedly, increasing the effectiveness of target destruction.
Another main aim of the invention is to solve the technical problem consisting in providing a solution for coordinating the initial "reference" positions in three dimensions of the device for triggering and focusing shots on a target point which is to be brought into coincidence with a target to be destroyed, e.g. a lithiasis, and a locating arm for locating the position of said target, said arm having a locating probe mounted at the free end thereof, and making it possible to detect imperfections in the three dimensional displacement of said device for triggering and focusing shots and of the locating arm thus making it possible to correct such imperfections, thereby improving, in unexpected manner, the accuracy of target location in three dimensions and the subsequent bringing into coincidence of the target to be destroyed with the target point, thus also giving rise to a concomitant improvement in the effectiveness of target destruction.
These new problems are solved for the first time by the present invention by providing a solution of negligible cost while increasing the number of targets that can be destroyed, e.g. tissues, lithiasis concentrations such as kidney stones or bile stones, etc., and reducing the duration of such shot treatment, by increasing the accuracy with which the target is located and the accuracy with which the target is brought into coincidence with the target point.